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The amount of net income (loss) from continuing operations per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) derived from continuing operations during the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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(LOSS) EARNINGS PER SHARE (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Numerator for basic and diluted earnings per share:
Net (loss) income	$ 27,377us-gaap_ProfitLoss	$ (93,337)us-gaap_ProfitLoss	$ 28,672us-gaap_ProfitLoss	$ 8,960us-gaap_ProfitLoss	$ 26,801us-gaap_ProfitLoss	$ 35,361us-gaap_ProfitLoss	$ 22,902us-gaap_ProfitLoss	$ 10,502us-gaap_ProfitLoss	$ (28,328)us-gaap_ProfitLoss	$ 95,566us-gaap_ProfitLoss	$ 129,674us-gaap_ProfitLoss
Denominator:
Weighted basic shares outstanding									60,311	60,574	53,884
Dilutive effect of equity-based compensation awards									0	154	195
Weighted dilutive shares outstanding									60,311	60,728	54,079
Basic earnings per share:
Basic earnings per share (in dollars per share)									$ (0.47)	$ 1.58	$ 2.41
Diluted earnings per share:
Diluted earnings per share (in dollars per share)									$ (0.47)	$ 1.57	$ 2.40